Objective 1:The use of XI VOCALTM in 3D volumetry measurements of fetal head and trunk of fetuses from 11 to 14 weeks gestation and known volume phantoms and its comparison with the conventional multiplanar and VOCALTM technique

Objective 2:The use of new modality of XI VOCALTM in 3D volumetry measurements of placenta from 11 to 14 weeks gestation and known volume phantoms and its comparison with the conventional multiplanar and VOCALTM technique

Objective 3:The use of 3DUS in the volumetry of first trimester pregnancy and in vitro study: comparison between two models of ultrasound machine

Objective 4:The use of 3DUS in the measurement of fetal, gestational sac and placenta quotient of fetuses at risk of homozygous αº-thalassemia (Hb Bart's disease) at 11 to 14 weeks' gestation